Generally, to change an engine coolant, the radiator drain cock is opened, and the coolant is discharged, but since the radiator drain cock is located in a lower position of the engine room, it is extremely hard to handle the drain cock, and complicated operations such as jack-up of vehicle were required.
A conventional constitution of such coolant changing apparatus is disclosed, for example, in the Japanese Laid-open Utility Model No. 4-66323.
That is, it relates to a radiator washing tank comprising a tank main body for accommodating a specified volume of liquid, a liquid feed port provided at the upper end of the tank main body, an opening valve in the lower part, a fitting cap detachably fitted to the filler port on the radiator upper tank provided at the lower end, and an air vent pipe opened near the opening valve at the lower end and opened above the tank main body at the upper end.
In this radiator washing tank, after discharging the liquid in the radiator by opening the drain cock of the drain port located below the lower tank of the radiator or at the side of the lower tank, the drain cock is closed, the filler cap of the filler port provided in the radiator upper tank is removed, the fitting cap at the lower end of the tank main body is fitted to the filler port opened by removing the filler cap by one-touch operation, the opening valve is opened, the liquid is fed in through the feed port of a relatively wide opening area at the upper end of the tank main body, then the liquid in the tank main body flows down by gravity, while the air in the radiator is released to the atmosphere through the upper opening of the tank main body through the air vent valve, and therefore the liquid in the tank flows smoothly into the radiator while releasing air, thereby washing the radiator and changing oil easily, and hence the job efficiency of washing and liquid change is enhanced, and the liquid feeding performance is notably improved, whereas the following problems existed.
Depending on the flow-down by gravity, the conventional apparatus took about 10 and 20 minutes to change oil, and the oil change efficiency was poor. In addition, it needed opening and closing of the radiator drain cock, and the same problems as mentioned above were not solved.